This invention relates generally to the area of leak detection in flanged joints. More particularly the invention relates to an apparatus and method for detecting a leak of hazardous material across a specific flanged joint in a multiflanged connection in refinery or chemical process equipment.
Gaskets are well known as sealing devices between two surfaces such as the flanged ends of pipe sections, reactor flow tubes, closures on chemical process vessels and the like. Generally such gaskets are retained between the two surfaces by bolts or other fasteners and their purpose is to prevent leakage of fluid material between the flanges. This is particularly important in processes involving flammable, hazardous, or toxic chemicals. With the growth of environmental regulations requiring control of fugitive emissions, the ability to rapidly detect leakage of these materials and to take the necessary corrective steps to stop such leakage is very important. Leak detection methods are currently employed in the chemical and petrochemical process areas but some of the methods used, such as sniffing each flange from the outside with an analytical device, have inherent safety-related drawbacks, as well as, being significantly time consuming. They also do not exclude contaminants that may be in the outdoors environment thereby possibly leading to incorrect results during the leakage check.
There are also gaskets on the market that claim to have leakage detection systems. These systems also have some drawbacks in that the exhausting system can be damaged and made inoperable by high-bolting pressure, particularly where the exhausting system utilizes a vacuum system. Contamination of samples can also occur with backflow of materials utilized in a vacuum system thereby leading to inaccurate results. Also, some of the commercial gaskets are flange specific in that they have to be tailor-made to fit the desired flange. This can lead to logistical problems where specific gaskets and specific flanges would have to be inventoried or specially ordered when one has to be replaced.